806 



SCIENCE 



[N. S. Vol. XXVII. No. 699 



products, cheapening of operations, and 

 turning low-grade products into high-grade 

 ones. 



I shall take up these four different lines 

 of work, one after another, somewhat in 

 detail. 



First— The buying and selling of ma- 

 terials according to analysis. I take it for 

 granted that no modern manufacturing 

 plant can run without power— power is in- 

 deed the chief distinguishing characteristic 

 of modern plants as contrasted with 

 ancient ones — and the principal source of 

 power stiU is steam under pressure, and 

 the heat necessary to generate steam is 

 derived from burning coal. In very recent 

 months plants have been constructed which 

 derive their power from gas engines 

 operating on producer gas, blast furnace 

 gas, etc., and such plants may operate 

 entirely without steam power. The de- 

 mands made upon the world's coal supply 

 for power have increased greatly in recent 

 years ; the coal supply can not last forever ; 

 and so, means must be devised for making 

 the coal supply last longer either by utiliz- 

 ing more of the energy or by working out 

 methods for substituting other sources of 

 energy for heat energy. The gas engine is 

 the result of efforts in the first direction 

 and the conversion of the gravitational 

 energy of falling water into electrical 

 energy is the result of the second. In spite 

 of the efforts now being made to conserve 

 the coal supply, the heat from burning 

 coal applied to steam boilers is still the 

 universal way of producing power. To 

 operate a boiler plant a good water supply 

 is necessary. There must not be too large 

 a quantity of incrusting substances in the 

 water, or scale wiU form in the boiler; the 

 water must not be too alkaline, or it will 

 prime or foam in the boiler. If only a 

 poor water supply is to be had, then the 

 chemist must provide a purification plant 

 or boiler compoiand which will prevent or 



minimize the formation of scale. The coal 

 received at all large plants is regularly 

 analyzed and by many the coal is con- 

 tracted for and bought on analysis. Thus 

 for the very fundamental process of 

 generating power for operating purposes, 

 the manufacturing plant must call in the 

 services of the chemist. 



But every plant buys large quantities of 

 supplies besides coal and water. For con- 

 struction work there is Portland cement, 

 which must be analyzed and tested; and 

 lime and sand are frequently examined by 

 the chemist. The railroad buys its iron 

 and steel, bronze and babbitt, brass and 

 tin according to analysis; the packing- 

 house buys its salt, sugar and vinegar in 

 this way; the soap factory buys oils and 

 tallows, caustic soda and soda ash, essential 

 oils and artificial perfumes entirely ac- 

 cording to composition and purity; the 

 sulphuric-acid plant buys its pyrites; the 

 fertilizer plant its potash salts; the glass 

 factory its sand, its lime, its soda; the 

 explosive factory its glycerine and nitric 

 acid, all according to the chemist's certi- 

 ficate. The analytical chemist has come to 

 be a factor of enormous importance in the 

 affairs of the commercial world. The very 

 standard of the basis of exchange is de- 

 termined by his assay; he analyzes every 

 product from stone and iron to food and 

 spices. 



Of course, the thought will occur to you r 

 How was manufacture and exchange con- 

 ducted at all in the days before chemistry 

 and chemists became so important? How 

 did manufacturers and business men get 

 along at aU? Well, they got along fairly 

 well then, but to-day I am afraid their 

 difficulties would be many. The keen 

 competition of to-day and the more elabo- 

 rate working up of by-products, yes the 

 greater complexity of modern society, have 

 brought about the change. StiU, even 

 to-day there are plants of fair size which 



